State of the art surgery for cosmetic hair transplantation involves redistributing permanent hair follicles from the back and sides of the head, to areas of hair loss. The most cosmetic method involves placing small bundles of hair—as they naturally occur—in small, closely approximated incisions on the scalp. Experience has shown the scalp has excellent blood supply and can support the transfer of at least 2000 of these bundles into 2000 small recipient sites on the scalp in one sitting. The bundled follicles are called “follicular unit grafts”, and the large numbers of grafts placed in a single surgery are referred to as megasessions. Each graft is carefully dissected from surrounding tissue, into a graft containing from 1-4 hairs, as it naturally occurred.
The one physical insult that can most impact graft survival is desiccation. Grafts are typically stored in a Petri dish surrounded in saline solution, prior to graft placement. Because of the risk of desiccation, most of the grafts are left in the Petri dish until just prior to placement. This usually involves transferring the graft from the Petri dish to the surgeon or the surgeon's assistant's finger, in preparation for placement into the scalp recipient site for transplantation. As will be appreciated, this is tedious and time consuming.
Various instruments have been developed for facilitating graft placement and are available commercially and/or described in the patent literature. They include the Choi implanter which is a spring loaded needle nose graft injector device. With a Choi implanter a single graft is threaded into the needle nose and injected into the incision. Thus, it is time consuming and expensive. One person must load the device prior to handing it off to the operating person in order to keep the flow smooth. An individual skilled operator can easily place grafts more quickly without the device, provided they do not have to turn and load grafts onto the finger from a Petri dish, and do repetitive unnecessary movements away from the patient's scalp.
Another hair transplant instrument is described in U.S. Pat. No. 5,584,851 to Banuchi. The Banuchi instrument does not actually implant grafts into the scalp. Rather, it is a shallow, rectangular tray, which narrows to a point in the front. The tray has separate ridges that form shallow troughs for the purpose of aligning grafts one above another. The tray does not allow for significant or immersible hydration of the grafts, although there is some. The operator is meant to pull the graft down through the shallow canal into the tip, and then into the incision. The tray has a limited graft holding capacity. It has a shallow design, and limited width, as this tray is intended to be hand held by the operator using the index finger and thumb. The design limits the operator's ability to utilize the hand which holds the Banuchi implanter, leaving it unavailable to perform any other function while doing this task. Also, should the operator loosen their grip or the tray slip, grafts are at risk for spillage.
U.S. Pat. Nos. 5,989,279 and 5,817,120 to Rassman describe a implantation device having a shallow tray with individual narrow channels each to hold a single graft. A spring-loaded mechanism advances the tray, while automatically unloading the graft into a pointed tip, which inserts the grafts into the recipient sites (either incisions or holes). This device reportedly is prone to jamming during use, has a limited capacity to hold grafts, has no capacity to keep grafts immersed in hydrating solution, and also is hand held.
U.S. Pat. No. 5,562,732 to Eisenberg describes a hair graft support tray system for mounting on the finger of a user. The Eisenberg hair graft support tray system includes a slidably mounted tray fixed to a tray support which includes a finger ring for retaining the tray on a finger of the user. The tray includes a plurality of grooves having drainage holes located in the grooves. Accordingly to Eisenberg, the tray is filled with micro- or mini-grafts and placed in storage in a saline solution until use. However, once the Eisenberg tray is removed from storage for use, there is nothing to retain the saline around the grafts, and the grafts are prone to dehydration. The drainage holes in the tray actually prevent immersible hydration from occurring and subject grafts to potential dessication during the insertion process of placement. Also, many users find the ring retention design of the Eisenberg support tray to be somewhat uncomfortable.
Yet other designs are described in U.S. Pat. No. 5,611,811 to Goldberg, U.S. Pat. Nos. 6,270,511 and 5,868,758 to Markman, U.S. Pat. No. 5,873,888 to Costango, U.S. Pat. Nos. 5,899,916 and 6,120,521 to Casparian.